The present invention relates to new 1,4-dihydro-4-oxo-3-quinoline derivatives that are antibacterial agents suitable for the treatment of bacterial and mycoplasma infections in mammals, including humans. The compounds of the invention exhibit unexpectedly favorable selectivity against procaryotic cells, as measured by their activity against procaryotic DNA gyrase versus mammalian topoisomerase II.
U.S. Pat. Nos. 4,775,668 and 4,861,779 refer to antibacterial compounds having the formula ##STR2## wherein R.sup.1 is hydrogen, a pharmaceutically acceptable cation, or alkyl; A is CH, CF, CCl or N; Y is alkyl, haloalkyl, cyclopropyl, vinyl, methoxy, N-methylamino, p-flurophenyl, p-hydroxyphenyl or p-aminophenyl; or A is carbon and is taken together with Y and the carbon and nitrogen to which A and Y are attached to form a five to seven membered ring which is optionally substituted; and R.sup.2 is a bridged-diazabicycloalkyl group.
Derwent anonymous research disclosure no. 88-103269/15 refers to compounds of the formula ##STR3## wherein R.sup.1 is (C.sub.1 -C.sub.3)alkyl, cyclopropyl, vinyl, hydroxyethyl, fluoroethyl, methoxy, amino, methylamino, dimethylamino, ethylamino, phenyl, 4-fluorophenyl or 2,4-difluorophenyl; R.sup.2 is hydrogen, (C.sub.1 -C.sub.4)alkyl or 5-methyl-2-oxo-1,3-dioxol-4-ylmethyl; R.sup.3 is methyl or one of eleven cyclic amino groups wherein one of said eleven cyclic amino groups is ##STR4## R.sup.4 is hydrogen, (C.sub.1 -C.sub.4) alkyl, hydroxyethyl, allyl, propargyl, CH.sub.2 COCH.sub.3, phenacyl, CHO, SCFCl.sub.2, SO.sub.2 CFCl.sub.2, SCOOMe, benzyl, 4-aminobenzyl or 5-methyl-2-oxo-1,3-dioxo-4-ylmethyl; R.sup.5 is hydrogen or methyl; R.sup.6 is hydrogen, (C.sub.1 -C.sub.4) alkyl, phenyl or CH.sub.2 OCH.sub.2 Ph; R.sup.7 is hydrogen, amino, methylamino, ethylamino, aminomethyl, methylaminomethyl, ethylaminomethyl, dimethylaminomethyl, hydroxy or hydroxymethyl; R.sup.8 is methyl, ethyl or chloro; X is fluyoro, chloro or nitro; Y is hydrogen, fluoro or amino; A is nitrogen or CR.sup.9 ; and R.sup.9 is hydrogen, alkoxy, (C.sub.1 -C.sub.3)alkylthio, halogen, methyl or nitro; or R.sup.1 and R.sup.9 are OCH.sub.2 CH(Me), SCH.sub.2 CH(Me), COCH.sub.2 CH(Me) or CH.sub.2 CH.sub.2 CH(Me). This broad generic disclosure includes several compounds of the present invention but does not teach or suggest their surprising and favorable selectivity as antibacterial agents against procaryotic versus eucaryotic cells.